source/effects/colorcurve.cpp

   1 #include <cmath>
   2 #include "color.h"
   3 #include "colorcurve.h"
   4 #include "mesh.h"
   5 #include "renderer.h"
   6 #include "shader.h"
   7 #include "texture2d.h"
   8
   9 using namespace std;
  10
  11 namespace Msp {
  12 namespace GL {
  13
  14 ColorCurve::ColorCurve():
  15         shprog("colorcurve.glsl"),
  16         quad(get_fullscreen_quad()),
  17         linear_sampler(get_linear_sampler()),
  18         nearest_sampler(get_nearest_sampler())
  19 {
  20         shdata.uniform("source", 0);
  21         shdata.uniform("curve", 1);
  22
  23         curve.storage(LUMINANCE8, 256, 1);
  24         texturing.attach(1, curve, linear_sampler.get());
  25
  26         set_exposure_adjust(0.0f);
  27         set_brightness_response(0.4f);
  28         set_linear();
  29 }
  30
  31 void ColorCurve::set_exposure_adjust(float e)
  32 {
  33         shdata.uniform("exposure", pow(2.0f, e));
  34 }
  35
  36 void ColorCurve::set_brightness_response(float b)
  37 {
  38         if(b<=0 || b>1)
  39                 throw invalid_argument("ColorCurve::set_brightness_response");
  40         float t = (b<1 ? pow(b, 1/(1-b)) : 0.0f);
  41         shdata.uniform("brightness_response", b, t, pow(t, b));
  42 }
  43
  44 void ColorCurve::set_gamma(float g)
  45 {
  46         if(g<0.1 || g>10)
  47                 throw invalid_argument("ColorCurve::set_gamma");
  48
  49         unsigned char curve_data[256];
  50         for(unsigned i=0; i<256; ++i)
  51                 curve_data[i] = pow(i/255.0f, 1/g)*255+0.5f;
  52         curve.image(0, curve_data);
  53 }
  54
  55 void ColorCurve::set_srgb()
  56 {
  57         unsigned char curve_data[256];
  58         curve_data[0] = 0;
  59         for(unsigned i=1; i<256; ++i)
  60                 curve_data[i] = to_srgb(i/255.0f)*255+0.5f;
  61         curve.image(0, curve_data);
  62 }
  63
  64 void ColorCurve::set_linear()
  65 {
  66         unsigned char curve_data[256];
  67         for(unsigned i=0; i<256; ++i)
  68                 curve_data[i] = i;
  69         curve.image(0, curve_data);
  70 }
  71
  72 void ColorCurve::render(Renderer &renderer, const Texture2D &color_buf, const Texture2D &)
  73 {
  74         texturing.attach(0, color_buf, nearest_sampler.get());
  75
  76         Renderer::Push push(renderer);
  77         renderer.set_shader_program(&shprog, &shdata);
  78         renderer.set_texturing(&texturing);
  79         quad->draw(renderer);
  80 }
  81
  82
  83 ColorCurve::Template::Template():
  84         exposure_adjust(0.0f),
  85         brightness_response(0.4f),
  86         gamma(1.0f),
  87         srgb(false)
  88 { }
  89
  90 ColorCurve *ColorCurve::Template::create(unsigned, unsigned) const
  91 {
  92         RefPtr<ColorCurve> colorcurve = new ColorCurve;
  93         colorcurve->set_exposure_adjust(exposure_adjust);
  94         colorcurve->set_brightness_response(brightness_response);
  95         if(srgb)
  96                 colorcurve->set_srgb();
  97         else
  98                 colorcurve->set_gamma(gamma);
  99         return colorcurve.release();
 100 }
 101
 102
 103 ColorCurve::Template::Loader::Loader(Template &t):
 104         DataFile::DerivedObjectLoader<Template, PostProcessor::Template::Loader>(t)
 105 {
 106         add("brightness_response", &Template::brightness_response);
 107         add("exposure_adjust", &Template::exposure_adjust);
 108         add("gamma", &Loader::gamma);
 109         add("srgb", &Loader::srgb);
 110 }
 111
 112 void ColorCurve::Template::Loader::gamma(float g)
 113 {
 114         obj.gamma = g;
 115         obj.srgb = false;
 116 }
 117
 118 void ColorCurve::Template::Loader::srgb()
 119 {
 120         obj.srgb = true;
 121 }
 122
 123 } // namespace GL
 124 } // namespace Msp